河北北方学院体育馆结构弹塑性动力响应分析

Research on elastic-plastic dynamic response of Hebei North University gymnasium

为研究大跨弦支穹顶空间结构中上部钢结构屋盖-下部混凝土结构组合体系协同工作性能,以河北北方学院体育馆为研究对象,分别建立体育馆弦支穹顶屋盖单体模型和考虑下部混凝土结构整体模型,通过对两种模型自振特性及小震、中震、罕遇地震和极罕遇地震下的动力响应对比分析,研究下部混凝土结构对上部钢屋盖结构工作性能影响。结果表明:考虑下部混凝土结构后,结构自振周期延长,振型多为上部钢屋盖振动;上下部结构刚度差异使上部屋盖产生类似"鞭梢效应"导致其水平位移明显增加,屋盖结构在水平地震耦合方向产生以屋盖顶点为中心呈反对称模式的凹陷与凸起变形;上下部结构协同工作对钢屋盖环索具有不利影响。

In order to study the cooperative performance of the composite system of the upper steel structure roof and the lower concrete structure in the long-span suspended dome space structure,the single model of the suspended dome roof of the gymnasium and the integral model of the lower concrete structure of the gymnasium are established respectively,taking the of Hebei North University stadium as the research object.Through the comparative analysis of the free vibration characteristics of the two models and the dynamic responses of frequent earthquake,design basic earthquake,rare earthquake and extremely rare earthquake,the influence of the lower concrete structure on the working performance of the upper steel roof structure is studied.The results show that:after considering the lower concrete structure,the natural vibration period of the structure is prolonged,and the mode of vibration is mostly the vibration of the upper steel roof;the stiffness difference between the upper and lower structures causes the similar"whiplash effect"of the upper roof.Horizontal displacement of roof structure increases obviously.In the direction of horizontal displacement coupling,the roof structure produces anti-symmetric sag and bulge deformation with roof vertex as the center,and the interaction between upper and lower parts has unfavorable effect on the force of ring cables of steel roof.